New York (CNN) - President Barack Obama on Sunday evening helped conclude remembrances of Americans who died in the September 11, 2001, terrorist attacks with a message of unity and resolve for the years ahead.

"These past 10 years underscore the bonds between all Americans. We have not succumbed to suspicion and mistrust," Obama said at the "Concert for Hope" at the Kennedy Center in Washington. "It will be said of us that we kept that faith; that we took a painful blow, and emerged stronger."